Photoinduced electron transfer in photosystems consisting of bis(6,6’-dimethoxy-3,3’-bipyridazine)(6,6’-bis [8-((4-methoxyphenyl)oxy)-3,6-dioxaoctyl-1-oxy]-3,3’-bipyridazine)ruthenium(II) dichloride (1), tris(6,6’-bis[8-((4-methoxyphenyl)oxy)-3,6-dioxaoctyl- 1-oxy]-3,3’-bipyridazine)ruthenium(II) dichloride (2a), tris(6,6’-bis[11-(4-methoxyphenyl)-3 ,6,9-trioxa-undecyl-1-oxy]-3,3’-bipyridazine)ruthenium(II) dichloride (2b), and tris(6-(8-hydroxy-3,6-dioxa-octane-1 -oxy)-6’-[8-((4-methoxyphenyl)oxy)-3,6-dioxaoctyl-1-oxy]-3,3’-bipyridazine)-1,3,5-benzenetricarboxylate-ruthenium(II) dichloride (3), with bis(N,N’-p-xylylene-4,4’-bipyridinium) (BXV(4+), 4) were examined. The series of photosensitizers include alkoxyanisyl donor components tethered to the photosensitizer sites, capable of generating donor-acceptor supramolecular complexes with BXV(4+) (4). Detailed analyses of the steady-state and time-resolved electron transfer quenching reveal a rapid intramolecular electron transfer quenching, k(sq), within the supramolecular assemblies formed between the photosensitizers and BXV(4+) (4) and a diffusional quenching, k(dq), Of the free photosensitizers by BXV(4+) (4). A comprehensive model that describes the electron transfer in the different photosystems and assumes the formation of supramolecular assemblies of variable stoichiomehries, SA(n), is formulated. Analysis of the experimental results according to the formulated model indicates that supramolecular complexes between 1-3 and BXV(4+) of variable stoichiometries exist in the different photosystems. Maximal supramolecular stoichiometries between 1, 2a and 3, and BXV(4+) (4), corresponding to N = 2, 6, and 3, respectively, contribute to the electron transfer quenching paths. The derived association constants of BXV(2+) to a single binding site in the photosensitizers 1, 2a, 2b, and 3 are 240, 100, 100, and 140 M(-1), respectively. The back electron transfer of the photogenerated redox products was followed in the different photosystems. Back electron transfer proceeds via two routes that include the intramolecular recombination, k(sr), within the supramolecular diads and diffusional recombination, k(dr), of free redox photoproducts. Detailed analysis of the back electron transfer in the different photosystems revealed that the non-covalently linked supramolecular assemblies, SA(n), act as static diads where electron-transfer quenching and recombination occurs in intact supramolecular structures despite the dynamic nature of the systems; The lifetime of the redox photoproducts Ru3+-BXV(. 3+) in the various systems is relatively long as compared to diad assemblies (0.56- 1.20 mu s). This originates from electrostatic repulsive interactions of the photoproducts within the supramolecular assemblies resulting in stretched conformations of the diads and spatial separation of the redox products.